Abstract: A key leveler and method of use for leveling keys on a musical instrument keyboard. A horizontal guide rail holding a gauge holder and height indicator is leveled over the keyboard. The gauge holder includes a downward-extending push rod for contacting each key. An index cylinder and spring adjustment screw adjust the spring force applied to the push rod. The index cylinder is selectively positionable in park, rest, and depressed positions for each key. The system also includes an electronic height indicator, a laptop computer, and a software program for simultaneously calculating the optimal shimming for each key.

Abstract: A method and apparatus for enclosing, controlling and suppressing the detonation of explosives in an explosion chamber is disclosed. The device comprises an elongate double-walled steel explosion chamber anchored to a concrete foundation, and having a double-walled access door for charging new workpieces, and a double-walled vent door for discharging the products of the explosion. The double walls of the chamber, access door and vent door are filled with granular shock damping material such as silica sand, and the floor of the chamber is covered with granular shock-damping bed such as pea gravel. Along the outside of the chamber are steel manifolds from which a linear array of vent pipes penetrates the double walls of the chamber, with each pipe terminating in a hardened steel orifice through which the explosion combustion products pass. Within the chamber, plastic polymer film bags containing water are suspended from steel wires over the explosive material, and at each end of the chamber.